
Data Sheet
July 2001
Forward Battery SLIC and Ringing Relay for TR-57 Applications
L9312 Line Interface and Line Access Circuit
Agere Systems Inc.
17
Electrical Characteristics
(continued)
ac Feed Characteristics
Table 8. ac Feed Characteristics
1. Set externally either by discrete external components or a third- or fourth-generation codec. Any complex impedance R1 + R2 || C between
150
and 1400
can be synthesized.
2. This parameter is not tested in production. It is guaranteed by design and device characterization.
3. VITR transconductance depends on the resistor from ITR to VTX. This gain assumes an ideal 6.34 k
, the recommended value. Positive cur-
rent is defined as the differential current flowing from PT to PR.
Parameter
Min
Typ
Max
Unit
ac Termination Impedance
1
Total Harmonic Distortion (200 Hz
—4 kHz)
2
:
Off-hook
On-hook
Transmit Gain
3
f = 1004 Hz, 1020 Hz:
PT/PR Current to VITR
Receive Gain, f = 1004 Hz, 1020 Hz Open Loop:
RCVP or RCVN to PT
—PR (gain = 8)
RCVP or RCVN to PT—PR (gain = 2)
ac Feed Resistance (includes internal SLIC ac resistance and
break switch resistance)
Gain vs. Frequency (transmit and receive)
2
900
= 2.16
μ
F Termi-
nation, 1004 Hz Reference:
200 Hz—300 Hz
300 Hz—3.4 kHz
3.4 kHz—20 kHz
20 kHz—266 kHz
Gain vs. Level (transmit and receive)
2
0 dBV Reference:
–
55 dB to +3.0 dB
Idle-channel Noise (tip/ring) 600
Termination:
Psophometric
C-Message
3 kHz Flat
Idle-channel Noise (VTX) 600
Termination:
Psophometric
C-Message
3 kHz Flat
150
600
1400
—
—
—
—
0.3
1.0
%
%
–
291
–
300
–
309
V/A
7.76
1.94
50
8
2
8.24
2.06
110
—
—
75
–
0.3
–
0.05
–
3.0
—
0
0
0
—
0.05
0.05
0.05
2.0
dB
dB
dB
dB
–
0.05
0
0.05
dB
—
—
—
–
82
8
—
–
77
13
20
dBmp
dBrnC
dBrn
—
—
—
–
82
8
—
–
77
13
20
dBmp
dBrnC
dBrn